[C23] Remove WG14 N2379 from the C status page

This paper was adopted at the Oct 2019 meeting in Ithaca, but the
changes from the paper were later removed (editorially) by the C
Floating Point study group due to being incorrect and unnecessary.

Author: AaronBallman

clang/www/c_status.html

@@ -747,11 +747,8 @@ <h2 id="c2x">C23 implementation status</h2>
       <td class="full" align="center">Clang 15</td>
     </tr>
     <!-- Oct 2019 Papers -->
-    <tr>
-      <td>*_IS_IEC_60559 feature test macros</td>
-      <td><a href="https://www.open-std.org/jtc1/sc22/wg14/www/docs/n2379.htm">N2379</a></td>
-      <td class="unknown" align="center">Unknown</td>
-    </tr>
+    <!-- WG14 N2379 *_IS_IEC_60559 feature test macros was removed by a later
+         change to C23. -->
     <tr>
       <td>Annex F.8 update for implementation extensions and rounding</td>
       <td><a href="https://www.open-std.org/jtc1/sc22/wg14/www/docs/n2384.pdf">N2384</a></td>